Friday, 21 May 2010

The idea that the brain changes and adapts according to how you use it, including through adulthood, is now widely accepted in psychology and neuroscience. Some of the most striking examples of this have come from studies of musicians. It's been shown, for instance, that string and keyboard players have more neural tissue given over to the control of the hands and fingers than do non-musicians. However, little researched until now is the brain re-organisation associated with professional singing.

Like the playing of a musical instrument, singing involves skilled muscle movements - indeed, more than 100 muscles are used - but there are also some differences between singing and instrument playing. For example, you can watch your own fingers tap out a tune on a keyboard but you can't 'see' your muscle coordination whilst singing.

Boris Kleber's team had 10 professional opera singers, 21 singing students and 18 non-singer controls lie in a brain scanner and sing 6 phrases from the first stanza of the Italian aria 'Caro mio ben'.

The most striking finding was that greater experience with opera singing was associated with more activation of the somatosensory cortex whilst singing. This part of the brain processes incoming signals from the body and the finding suggests that singing expertise is particularly associated with enhanced processing of where the vocal muscles are positioned in space. This makes sense given that you can't 'see' yourself sing and must instead rely on feedback from the vocal muscles.

As you might expect, studies with people who can play musical instruments have generally found increased activation of the primary motor cortex - a key brain area involved in sending commands to the muscles. However, in the current study, it was only the most experienced opera singers who showed exaggerated activity in this brain area.

Another neural characteristic associated with expertise in opera singing was more activity in the dorsolateral prefrontal cortex, an area involved in working memory. The researchers speculated this could be because opera singing usually involves singing and acting at the same time, so the experts may have developed 'more resources for performance monitoring'.

More singing experience was also linked with more activation in the inferior parietal cortex, possibly reflecting comparison of 'the actual kinesthetic feedback with the kinesthetic "expectation" for the produced sound', and with greater activation of the cerebellum - that's the cauliflower shaped structure hanging off back of the brain, which is known to be involved in coordination.

'Opera singers must routinely adapt their vocal system to unusual postures during singing as part of their stage play,' the researchers said. 'It is likely that this group has a particularly developed adaptive system to cope with such demands, which might require increased cerebellar involvement.'
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Anonymous: you say they did not find activation in the somatosensory cortex. This is incorrect. I quote from the paper: "the total practice in classical singing did not reveal changes in M1 [primary motor cortex] but was strongly correlated with increased activation in ventral primary somatosensory cortex. The reported results suggest that somatosensory feedback might play a particularly important role in the development of classical singing skills.